Although the cost of ROM memory per byte is decreasing, it remains a competitively significant factor in the design of microprocessor control logic driving wire matrix printers. Indeed, the prior art exemplified by Reghbati, "An Overview of Data Compression Techniques", IEEE Computers, Apr. 1981, at pp. 71-75, describes high density high capacity storage where billions of bytes can be crammed into the same memory or the amount of memory can be reduced for the same information volume. In high capacity storage, compression techniques of choice include special codes driven by source symbol statistics or selected enumerative or combinatorial attributes of source symbol strings. Relatedly, where two dimensional arrays of images are black/white encoded by means of black dots in an otherwise white field, the compression for high capacity storage uses special purposes statistical, predictive, or character recognition codes as found in Arps, U.S. Pat. No. 4,028,731, issued June 7, 1977; however, the implementation complexity and expense justifiable in the gigabyte volumes of on-line direct access storage might very well drive a utilizing printer subsystem out of the market.